De-icing apparatus for airplanes



Odi. 15, 1940. W C, CLAY 2,217,570

DE-ICING APPARATUS FOR AIRPLANES l Filed March 10, 1939 v *FK 'd-f 6 i me/wko@ Clay.

Patented Oct. 15, 1940 UNITED STATES PATENT OFFICE 11E-rome. nPrAnATUs' Fon AiitrLANEs 'Willlanr Clay, Buckroe Beach, Va. Appucatlonmah 1o, 1939, sei-ni No. gehost Momma (ol. 24a-134) m type, owing to the fact that, when flying under ice forming conditions, liquid particles in theL airstream not only congeal on the spinner'but also tend to collect and solidify around the roots of the propeller blades and prevent proper funclf tioning of the pitch changing mechanism. Furthermore, the accretion of ice on the spinner and nose ofthe fuselage materially increases head resistance and consequently retards the speed of the airplane. .20 The object of the invention is to overcome these objectionable features by providing a rotating shield or disk disposed in advance of the spinner or nose of the fuselage and which will intercept any and all of the liquid particles in the 2;, aix-stream that normally would fall or impinge on the surface of thespinner; nose or otherv exposed surface of an airplane.

A further object of the invention is to provide a flexible shield or disk mounted to revolve with 3g the spinner and susceptible of radial stretch or distention under the innuence of centrifugal force to automatically loosen and dislodge any particles of liquid, ice or snow in the airstream which may be deposited thereon when the air- 35 plane is in flight.

A further object is to provide a de-icing shield or disk comprising a plurality of ilat flexible members formed of rubber or other elastic material and each provided with a series of radiat- 40 ing slits or incisions dening independent stretchable segments,l said members being so constructed and arranged that the slitted portion of one member overlaps the solid portion or hub of an adjacent member whereby to present 45 ade-icing surface, the effective-area of which approximates .the 'diameter of the shield.

A still further object of the Iinvention is to provide a de-icing shield of simple and inexpensive construction capable oi' ybeing quickly at- 50 tached to the spinner or other exposed surface.

of an airplane without necessitating any material structural change therein andwhich may be rotated either by the spinner or by an auxiliary motor or other source of power on the airplane. 55 In the accompanying drawing forming a part slits or incisions of this specification and in which. similar numerals of reference indicate correspondingparts in all the figures of the drawing: Y

Figure l is a perspective .viewl of an airplane propeller of the variable pitch blade type showing the de-icing shield or disk inn-position on the spinner thereof,

Figure 2 is an enlarged transverse sectional view taken onthelineZf-Z ofFigure 1,

Figure 31s a detail vertical sectional view illus- 10 .trating a de-icing shield ofthe lsingle disk type,A

and .v

Figure 4 is a side elevation, partly, in section. showing the de-icing shield mounted on the nose of an airplane. 1. 1 15 The improved de-icingi shield Aor disk forming the subject-matter of the present invention may kbe used 1n connectionfwith'anysurface of an and in Figure 1 'is shown applied to a standard propeller of thefeathering or vari-V able pitch blade'type, in which 5 designates the propeller hub, 6 the 4blades and l the spinner secured to and mounted for rotationwith the hub inthe usual manner. f 25 The device comprises a fiat flexible 4inner member or disk 8 preferably oi'a diameter equal to or `slightly larger thanthe diameter rof the spinner 1 so as eiiectually to intercept any and all liquid particles in the airstreani that ynor o mally would fall or impinge on the exposed surface of said spinner. The shield or disk 8 is circular in contour and preferably formed of rubber or other suitablefmaterlal possessingsufcient inherent velasticity to cause dlstentionror 35 stretching of said material by centrifugal force when liquid particles are deposited thereon during rotation 'of the disk. w-

The material of which the disk isv formed is relatively thick at its point of attachment tothe 40 spinner to form a plano-convex hub portion 9 and then gradually decreases in thickness from the hub to the outer periphery of the disk to form a vflexible skirt havingy spaced radiating Ilitherein and defining inde- 4'5 pendent stretchable portions or segments Il. The slits or incisions i0 extend entirely through the disk and sever the skirt 'along radial lines from the hub to the' periphery of said disk so that the segments Il are free to stretch inde- 50 `pendently of each other, thereby to loosen ancl dislodge any snow or liquid particles that may be deposited thereon. f

Associated with the 'inner disk 8 is a Smaller outer disk I2 similar in construction to the in- 55 ner disk and so positioned with respect thereto that the flexible segments Il of the outer disk will overlap the hub portion l of the inner disk and thus present a substantially unbroken de,- icing surface in advance `of the spinner for intercepting liquid particles in the airstream and consequently prevent snow and ice from finding lodgment on the spinner or around the roots of the propeller blades 6 and interfering with the pitch changing mechanism thereof.

Extending laterally from the free end of the spinner 1 and preferably formed integral therewith is a bolt or stud il and the hubs of the inner and outer disks are provided with registering openings I5 adapted to receive said stud. Interposed between the flat face of the inner disk 8 and the spinner 'I is a spacing washer I6 and threaded on the outer end of the bolt Il is a clamping nut i1 which engages a washer I8 and serves to clamp the'disks firmly in position on the-spinner so as to rotate therewith. The inner face of the spacing washer I6 is preferably curved at I9 to conform to the outer surface of the' nose of the spinner 1, as best shown in Figure 4 of the drawing.

It will be noted that the inner and outer disks are assembled on the supporting stud I4 with the convex faces of the hubs thereof disposed in contact with each other so as to properly separate the outer edges of the disks and render the employment of an intermediate spacing washer unnecessary.

In operation, when an airplane is flying under ice forming conditions, the rotating shield, owing to its size and position on the spinner, will intercept any liquid particles in the airstream tending to collect on said spinner. Should ice form on the flexible segments of the shield, the additional weight of the ice accretions thereon augmented by centrifugal force incident to rotation of the shield, will distend or stretch said segments radially so as to cause the ice to loosen and separate from the segments and be thrown off harmlessly without allowing any deposit of ice on the spinner or around the roots of the propeller blades so that head resistance is reduced to a minimum and proper functioning of the pitch changing mechanism assured.

In Figure 3 of the drawing, there is illustrated in which but a 20 is used,'said shield or a modified form of the invention, single shield or disk .disk being supported on the nose of the spinner by a removable stud or bolt 2 I, the head of which is provided with anchoring spurs 22 adapted io bite into the inner surface of the spinner o prevent rotation of said bolt. It will'be understood, however, that be formed of any desired number of flexible disks and that the supporting studs for the disks may be formed integral with the spinner or separate therefrom as desired.

The de-icing shield is also applicable to the fuselage of an airplane to prevent ice formation Ion the nose thereof, and in Figure 4 of the drawing, I have shown an embodiment of the invention capable of performing that function. When the device is used for this purpose, I provide a suitable motor 23 preferably mounted in the pitch changing mechanism the de-icing shield maythe terminals 2l' of the electric conductors may extend to a suitable switch located inthe cabin of the fuselage so that, when the plane is travcling under ice forming.conditions by merely closing the switch, the shield will be caused to rotate in advance of the fuselage and intercept any liquid particles in the airstream which otherwise would Vfall on the nose and form ice thereon. When the shield shown in Figure 4 is not in use. the switch is actuated to cut ofi current .to the motor, and inasmuch as the shield 21 is formed of flexible material, the pressure of air on the shield will flatten said shield against the nose of the fuselage, as indicated by dotted lines at 30, so that the shield will not offer any drag or headresistance during the flight of the air-l plane. As the lodgment or formation of ice or snow around the roots of the propeller blades materially interferes with the pitch changing mechanism thereof and sometimes causes said to cease functioning entirely, thelprovision of a shield to avoid these objectionable features is very desirable as a safety factor when flying under ice forming conditions.

While I have shown and described the shield in connection with the spinner and nose of an airplane. it will, of course, be understood that said de-icing shield may be used in connection with any surface of an airplane exposed to ice forming conditions in an airstream. It will also be understood that the diameter of the shield may be varied at will without departing from the spirit of the invention.

Having thus described the invention, what is claimed as new is:

1. In an airplane, the combination with a mem-a ber having a surface exposed to ice forming conditions, of a substantially flat radially expansible shield mounted for rotation on said member.

2. In an airplane, the combination with a-member having a surface exposed to ice forming con-` ditions, of a substantially fiat elastic disk mounted for rotation in advance of said member and provided with independent segments movable to distended position when ice forms thereon to loosen and separate the ice therefrom. l

3. In an airplane, the combination with a member having a surface exposed to ice forming conditions, of a substantially flat elastic shield mounted for rotation on said member in advance thereof and provided with radial incisions defining independent segments adapted to be stretched radially by centrifugal force to dislodge ice deposits thereon.

4. In an airplane, the combination with a member having a surface exposed to ice forming conditions, of an elastic disk mounted for rotation in advance of said member and provided with normally closed radial slits intersecting the periphery of the disk.

5. In an airplane, the combination with a member having a surface exposed to ice forming conditions, of a substantially fiat radially expansible shield mounted for rotation in advance of said member and provided with peripheral portions independently distensible radially under the iniiuence of centrifugal force and the weight of ice deposited thereon for loosening and separating the ice from said portions.

6. In an airplane, the combination with a member having a surface exposed to ice forming conditions, of a radially expansible shield mounted for rotation in advance of said member and comprising a plurality of substantially fiat elastic disks of different Sizes each having radially slit peripheral portions-the slit portions of onel disk overlapping the slit portions of an adjacent disk.

7. In an airplane, the combination with a member having a surface exposed to ice forming conditions, a supporting stud carried by said member, and a plurality of elastic disks mounted on the stud and provided with radial slits defining independently distensible sections.

8. In an airplane propeller, the combination with a spinner, of a support carried by the spin ner, anda substantially flat radially expansible shield independent of the spinner v'mounted on the support in advance of said spinner -to turn therewith for preventing formation of ice on said spinner.

9. In an airplane, the combination withla propeller and spinner. of a support projecting from the end of the spinner, and a exlble shield independent of the spinner mounted on the support to turn with said spinner, said shield being of a diameter greater than the maximum diameter of the spinner thereby to intercept liquid particles in an airstream and prevent the formation of ice on the spinner andl around the roots of the propeller blades.

10. A de-icingv attachment for airplanes comprising a radially expansible elastic member having incisions extending inwardly from the peripheral edge thereof and defining separate portions adapted to be stretched by centrifugal force when ice forms thereon, and means for supporting said member for rotation on the exposed surface of an airplane.

11. A de-icing attachment for airplanes comprising a plurality of rotating elastic members of dierent sizes disposed one in advance of the other and each provided with normally closed radial slits extending inwardly from the periphery thereof to form a flexible skirt. said skirt being adapted to be stretched by centrifugal force when ice forms thereon to separate the ice therefrom, and means for supporting said members for and deflningdistensible segments, a washer interposed between one of the disks and the adjacent face of the spinner, and a nut engaging threads on the stud and bearing against the other disk.

13. In an airplane, the combination with a spinner, a supporting stud mountedl on the spinner,. a plurality of flexible disks of different sizes fitted on the stud and each having a solid planoconvex hub portion and a flexible skirt integral therewith, each skirt being formed with radiating incisions dening independent vdistensible segments, said disks being disposed one in advance of the other with the distensible sections on one disk overlapping the junction of the hub portion and distensible segments of an adjacent disk.

14. In an airplane, the combination with 'a propeller and spinner, of a substantially flat radially slitted elastic disk independent of the spinner disposed in advance of said spinner and mounted to turn therewith, said disk being of sufficient size to intercept liquid particles in an airstream and thereby prevent the formation of ice on the spinner and around the roots of the propeller blades.

WILLIAM C. CLAY.

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